1. Field of the Invention
The present invention relates to a cam apparatus for performing processing such as punching, bending, and the like with respect to a workpiece such as a thin plate by means of a tool fitted to a cam slide by causing the cam slide to slide by a cam driver.
2. Description of the Related Art
In a cam apparatus of a suspended or aerial cam type including, for example, a cam driver having a sliding surface with a V-shaped cross section and attached to a lower die base by means of a knock pin, screws, and the like, a cam slide having a sliding surface of a shape complementary to that sliding surface, and a cam-slide supporting base which movably supports the cam slide and is attached to an upper die base by means of the knock pin, screws, and the like, there is an advantage in that it is possible to mount the cam slide on the cam driver in a state in which the cam slide is removed from the cam-slide supporting base and the upper die is not disposed, as well as to effect the positioning, i.e., cutting edge adjustment, of a tool such as a piercing punch attached to the cam slide with respect to, for example, a button die provided in the lower die.
After the cutting edge adjustment, if the cam-slide supporting base is attached to the upper die base by means of the knock pin, screws, and the like, and if the cam slide is attached to the cam-slide supporting base, there are cases where, due to an error in attaching the cam-slide supporting base to the upper die base, an error in attaching the cam slide to the cam-slide supporting base, an error in the disposition of the upper die and the lower die, and the like, the once-set positions of the piercing punch and the button die become offset by more than an allowance, e.g., by more than 0.04 mm to 0.05 mm on one side in the case of the piercing of a thin plate, and the mutual sliding surfaces of the cam driver and the cam slide fail to come into desired surface contact with each other, causing one-sided contact. This can result in the occurrence of burrs in actual processing and the possible incidence of breakage of the piercing punch as it rides over the button die.